| Great Skua | |
|---|---|
 | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Charadriiformes |
| Family: | Stercorariidae |
| Genus: | Stercorarius |
| Species: | Stercorarius skua |
The Great Skua (Stercorarius skua), also called Bonxie in Britain, is a large seabird in the family Stercorariidae.
Description[]
Weighing 1-2 kg and measuring 51-57 cm in length and 145-155 cm in wingspan, the Great Skua is largest of the skuas found in the Northern Hemisphere. It is roughly the size of a Herring Gull, but stockier, barrel-chested, with a short, wedge-shaped tail, and relatively broad, rounded wings. The adult is dark brown mottled with fawn, paler on the neck and chest and darker on the crown, with a white crescent-shaped patch at the base of the remiges. The female is usually slightly larger than the male. Juveniles, usually darker and more uniformly coloured, may be blackish or reddish with a dark head, and have a smaller wing patch. The Great Skua has a sturdy, hooked bill and large, webbed feet with short, sharp claws.
Voice[]
The Great Skua's calls include a loud, guttural "tak-tak", a strident "keerr" and a barking "ak-ak-ak". This bird is most vocal near at its nesting site.
Behaviour[]
It generally flies slowly, with deep wingbeats, like a large gull, but is capable of quick and nimble aerial pursuits. It can also swim and dive underwater. It is opportunistic, aggressive and highly territorial. It mostly uses its bill to attack its victims, as it is unable to grab and hold prey in its talons like birds of prey do; however, it may still use its claws as a weapon. The Great Skua has a lifespan of up to 30 years.
Feeding[]
This bird feeds on fish, crustaceans, molluscs, offal, small terrestrial animals, eggs and chicks. It is known for its habit of chasing other seabirds in flight to make them drop their catch, a behaviour known as kleptoparasitism. Sometimes it will even kill and eat adult birds, especially auks.
Breeding[]
The breeding season begins around April and may last until August. Great Skua pairs nest alone or in loose colonies in which each couple has access to a large territory. The Great Skua nests on the ground, laying a clutch of 2 beige or olive eggs with dark spotting in a depression concealed in vegetation. The incubation period lasts 28-30 days, with both parents brooding the eggs. The young are semi-altricial and become independent at 6-7 weeks of life. One of the most aggressive seabirds of the north Atlantic, the Great Skua will defend its nest fiercely, swooping down violently on any intruders, including humans, which it has been known to injure.
Distribution and habitat[]
The Great Skua breeds along the European coasts of the north Atlantic Ocean, specifically in Iceland, the Faroe Islands, the Scottish islands and Norway. A few also breed in mainland Scotland and Ireland. It is a coastal species often found near seabird colonies during the breeding season. In winter, Great Skuas scatter across the Atlantic, reaching the coasts of the Americas and Africa, with some even reaching the Pacific.